High dietary sodium intake is linked to incident hypertension, stroke, heart failure and kidney disease. U.S. federal guidelines advocate daily sodium intake of less than 2,300 milligrams (mg) with further reduction to 1,500 mg in persons who are 51 and older and those of any age who are African American and/or have hypertension, diabetes, or chronic kidney disease. The estimated average sodium intake for Americans is 3,400 mg per day. In recent years, consumption of pre-processed and restaurant foods has substantially increased, and more than 75% of sodium in the average U.S. diet now comes from these sources. Most patients prescribed a low sodium diet either do not understand or possess the information about sodium content of the foods they eat and current IT approaches to reduce sodium intake focus solely on counting the amount of dietary sodium eaten. We will develop a mobile application that incorporates geofencing technology and provides just-in-time mobile push messages at the 2 main locations hypertensive patients interact with processed and prepared foods, at a grocery store or eating at a restaurant. Geofencing technology allows the mobile application to be aware of the user's location and provide location-specific messages, vital for the just-in-time nature of the intervention. The proposed project will establish a geofencing based adaptive notification message system for the mobile application using participant feedback to facilitate reducing dietary sodium intake and will then determine the effectiveness of the mobile application in helping hypertensive patients reduce dietary sodium intake and feel more confident in following a low sodium diet. These data will be crucial for a planned randomized clinical trial to test the sustained effects of the mobile application on blood pressure and sodium intake. The application of this technological approach has positive implications in improving self-management and reducing disease morbidity.